MP Yvette Cooper claims bosses at troubled Kellingley Colliery are refusing to speak to potential investors to secure a long-term future for the site.
The Pontefract and Castleford MP has called on pit operator UK Coal to meet interested parties to secure a future beyond next year.
But UK Coal has disputed the claim saying it is “nonsense.”
Ms Cooper said: “Over the past few weeks I’ve met several potential investors who have all said the same thing - bosses at UK Coal and government ministers won’t engage with them or give them the information they need to consider a serious offer that could help keep Kellingley open for much longer.
“I’ve written to the company and the government to demand change. There are 700 skilled jobs at risk and Britain will still rely on coal for years to come.”
“UK Coal and the government should be doing everything they canto explore every option possible to keep the mine open.”
The company - backed by £20m of investment from the government and private sector - plans to close the pit, with the loss of 700 jobs by December 2015.
Ms Cooper added: “The clock is ticking because the first redundancies are due.
“I won’t stop fighting for this; it’s what the miners deserve and it’s what’s best for our area and for the country.
A spokesman for UK Coal, said: “Rumours that UK Coal is ignoring approaches from potential investors in the business continue and remain complete nonsense.
“Directors have a duty to listen to any approach from potential investors and all have been spoken to.
“The only deal currently available to us is the managed closure plan which we desperately need to finalise to avoid the immediate collapse of the business.”